Global sea levels are rising at a faster pace than previously predicted as a result of melting ice sheets in Greenland and Antarctica, new satellite research shows.

At the current rate, the world’s oceans on average will be at least 65 centimetres higher by the end of the century compared to today, according to researchers who published in Monday’s Proceedings of the National Academies of Sciences.

The research, based on 25 years of satellite data, shows that pace is quickening every year, mainly from the melting of massive ice sheets.

It reported a seven centimetre rise in sea levels since 1993, which confirms scientists’ computer simulations and is in line with predictions from the United Nations, which releases regular climate change reports.

However, according to scientists these projections are a conservative estimate and it is likely to be higher.

Changes in sea level observed between 1992 and 2014. Photo: NASA

“It’s a big deal,” University of Colorado lead author Steve Nerem said.

“This acceleration, driven mainly by accelerated melting in Greenland and Antarctica, has the potential to double the total sea level rise by 2100 as compared to projections that assume a constant rate, to more than 60 centimetres instead of about 30.”

The projection is in line with climate models used in the latest International Panel on Climate Change report, which predicts a sea level rise of between 52cm and 98cm by 2100, if greenhouse emissions continue without reduction.

Scientists also added even small changes in sea levels can lead to flooding and erosion.

“Any flooding concerns that coastal communities have for 2100 may occur over the next few decades,” Oregon State University coastal flooding expert Katy Serafin said.

Of the seven centimetres of sea level rise in the past quarter century, about 55 per cent is from warmer water expanding, and the rest is from melting ice.

But the process is accelerating, and more than three-quarters of that acceleration since 1993 is due to melting ice sheets in Greenland and Antarctica, the study shows.

Satellite data is said to provide a more precise estimate of global sea levels over the normal tide-gauge data, which is predominately used to measure open ocean levels.

-with AAP